Cooling unit using ionic wind and led lighting unit including the cooling unit

ABSTRACT

A cooling unit includes a heat radiant having a heat radiating plate contacting a heating element, and a plurality of heat radiation pins protruding from the heat radiating plate and separated from each other with predetermined intervals therebetween, and formed of an electrical insulating material; and an ionic wind generating unit comprising a corona emitter electrode contacting at least one of the heat radiation pins, a collector electrode facing the corona emitter electrode, and a power unit to connect the corona emitter electrode to the collector electrode and to apply a high voltage to the corona emitter electrode. Thus, the corona emitter electrode and the collector electrode of the ionic wind generating unit may be directly attached to the heat radiant, and a small and light cooling unit may be formed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Korean Patent Application No.10-2011-0001798, filed on Jan. 7, 2011, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND

1. Field

One or more aspects of an embodiment or embodiments relate to a coolingunit using ionic wind and a light emitting diode (LED) lighting unitincluding the cooling unit, and more particularly, to a cooling unithaving an improved cooling performance by using an ionic wind generatingapparatus and an LED lighting unit including the cooling unit.

2. Description of the Related Art

In general, electronic devices generate a lot of heat when operated, andthe generated heat is one of reasons degrading electronic devices. Thus,a heat radiation unit is an essential element in electronic devices.

In order to cool down a heat radiation structure attached to a heatingdevice in a conventional electronic device, natural convection or acooling fan is used. However, according to a conventional naturalconvection method, it is difficult to cool down a heat radiationstructure effectively, and according to a cooling fan method, noise andpower consumption may increase.

Recently, cooling devices using ionic wind instead of using a coolingfan have been actively developed due to having advantages, for example,such as low noise and low power consumption. Ionic wind is generatedwhen a high voltage is applied to an electrode, for example, such as aprobe or a thin wire to generate a corona discharge and thus ionizedair, and then nearby air is moved by a strong electric field.

That is, when ions are generated by a corona discharge generated byapplying a high voltage to a wire or probe type emitter and areaccelerated by Coulomb force due to an electric field between theemitter and a collector electrode, ionic wind flows from the emitter toa/the collector electrode, thereby transferring motion force to nearbyair molecules.

A cooling operation using ionic wind does not have any element that isdriven by a motor, unlike a conventional cooling fan, and thus, variousadvantages, for example, such as high reliability, low noise, low powerconsumption, and small size may be obtained. A conventional ionic windcooling apparatus has a structure in which a plurality of metalelectrodes are located around a metal heat radiation structure atpredetermined intervals to generate ionic wind. When a conventional heatradiation structure is formed of a conductive material, for example,such as aluminum or copper, it is difficult to couple a conventionalionic wind cooling apparatus directly to the heat radiation structure.Also, a corona emitter electrode of a high voltage should be separatedfrom a conductive heat radiation structure by a predetermined distance.Thus, an additional structure to support a corona emitter electrode andelectrically insulating the corona emitter electrode from a heatradiation structure is necessary in a conventional ionic wind coolingapparatus. Therefore, there is a limitation in reducing a size of anionic wind cooling apparatus that is coupled to a heat radiationstructure.

SUMMARY

One or more aspects of an embodiment or embodiments provide a coolingunit in which an ionic wind generating unit is efficiently attached to aheat radiation structure so as to reduce an overall size, and a lightemitting diode (LED) lighting unit including the cooling unit.

According to an aspect of an embodiment or embodiments, there isprovided a cooling unit including: a heat radiant having a heatradiating plate contacting a heating element, and a plurality of heatradiation pins protruding from the heat radiating plate and separatedfrom each other with predetermined intervals therebetween, and formed ofan electrical insulating material; and an ionic wind generating unitincluding a corona emitter electrode contacting at least one of the heatradiation pins, a collector electrode facing the corona emitterelectrode, and a power unit to connect the corona emitter electrode tothe collector electrode and apply a high voltage to the corona emitterelectrode.

According to another aspect of an embodiment or embodiments, there isprovided a light emitting diode (LED) lighting unit including: at leastone LED; a cooling unit including a plurality of heat radiation pins toradiate heat generated by the LED; and an ionic wind generating unitincluding a corona emitter electrode contacting at least one of the heatradiation pins, a collector electrode facing the corona emitterelectrode, and a power unit to connect the corona emitter electrode tothe collector electrode and apply a high voltage to the corona emitterelectrode.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee. The above and other features of an embodiment orembodiments will become more apparent by describing in detail exemplaryembodiments thereof with reference to the attached drawings in which:

FIG. 1 is a perspective view of a cooling unit according to anembodiment;

FIG. 2 is a cross-sectional view of a cooling unit according to anotherembodiment;

FIG. 3 is a cross-sectional view of a cooling unit according to anotherembodiment;

FIG. 4 is a cross-sectional view of a cooling unit according to anotherembodiment;

FIG. 5 is a cross-sectional view of a cooling unit according to anotherembodiment;

FIG. 6 is a plan view of a cooling unit according to another embodiment;

FIG. 7 is a perspective view of a corona emitter electrode according toan embodiment;

FIG. 8 is a perspective view of a cooling unit according to anotherembodiment;

FIG. 9 is a perspective view of a light emitting diode (LED) lightingunit including an ionic wind cooling device according to an embodiment;

FIG. 10 is a graph illustrating performance of a cooling unit accordingto an embodiment;

FIG. 11 is a graph showing results of measuring velocity variation ofionic wind by a cooling unit according to an embodiment; and

FIG. 12 is a graph showing results of measuring temperature variation ofa heating element when a cooling unit according to an embodimentoperates.

DETAILED DESCRIPTION

FIG. 1 is a perspective view of a cooling unit 100 according to anembodiment, FIG. 2 is a cross-sectional view of a cooling unit 200according to another embodiment, and FIG. 3 is a cross-sectional view ofa cooling unit 300 according to another embodiment.

Referring to FIG. 1, the cooling unit 100 includes a heat radiant 110contacting a heating element H to radiate heat generated from theheating element H, and an ionic wind generating unit 120 to generateionic wind and making the ionic wind flow on the heat radiant 110 inorder to enhance the heat radiating operation of the heat radiant 110.

The heat radiant 110 includes a heat radiating plate 111 contacting theheating element H, and a plurality of heat radiation pins 112 protrudinga predetermined length from the heat radiating plate 111. The pluralityof heat radiation pins 112 are separated from each other by apredetermined interval along a length of the heating element H, andspace portions 113 are formed between the heat radiation pins 112. Theheat radiant 110 may be attached or bonded to the heating element H byusing a thermal interface material (TIM) having a high thermalconductivity. Otherwise, the heat radiant 110 may be integrally formedwith a material used to package the heating element H.

The heat radiant 110 may be formed of an electrical insulating material,for example, such as ceramic, or may be formed of a conductive material(e.g., copper or aluminum) and coated with ceramic. Ceramic materialshave high thermal conductivities and low electrical conductivities, andwhen the heat radiant 110 is formed of a ceramic material, a coronaemitter electrode and a collector electrode may be directly attached tothe heat radiant 110.

The ionic wind generating unit 120 includes a corona emitter electrode121 that is attached to a side surface of at least one heat radiationpin 112 along a length of the at least one heat radiation pin 112, acollector electrode 122 installed on another heat radiation pin 112 thatis adjacent to the at least one heat radiation pin 112 on which thecorona emitter electrode 121 is installed to face the corona emitterelectrode 121, and a power unit 123 connected to the corona emitterelectrode 121 and the collector electrode 122 to apply a relatively highvoltage to the corona emitter electrode 121.

The corona emitter electrode 121 may be formed of a wire having acircular cross-section. The corona emitter electrode 121 may be formedof a fine cylindrical wire having a diameter of about 10 μm to about 500μm, or may be formed by patterning an electrode having a sharp edgethrough an etching process and then directly attached to a side surfaceof one heat radiation pin 112 so as to concentrate an electric field onthe side surface of the heat radiation pin 112.

The corona emitter electrode 121 may be disposed on a portion of a sidesurface of at least one heat radiation pin 112. In FIG. 1, the coronaemitter electrode 121 is installed on an upper portion of the sidesurface of the at least one heat radiation pin 112; however, the coronaemitter electrode 121 may be installed on an intermediate or lowerportion of the side surface of the at least one heat radiation pin 112,as denoted by dotted lines. When the corona emitter electrode 121 isinstalled around the lower portion of the at least one heat radiationpin 112, a degree to which other electronic components are affected byelectric field interference generated by the relatively high voltageapplied to the corona emitter electrode 121 may be minimized, and anelectric shock that may occur when a person is negligent may beprevented.

The collector electrode 122 is installed to face the corona emitterelectrode 121, and may be installed to cover a side surface of at leastone heat radiation pin 112 that is adjacent to another heat radiationpin 112 on which the corona emitter electrode 121 is installed.

The power unit 123 applies the relatively high voltage to the coronaemitter electrode 121. When a relatively high voltage of a few kiloVolts (kV) is applied to the corona emitter electrode 121 from the powerunit 123, the corona emitter electrode 121 may generate a positivecorona discharge or a negative corona discharge.

Locations where the corona emitter electrode 121 and the collectorelectrode 122 are installed are not limited to the locations shown inFIG. 1, and may be modified variously in consideration of heat radiatingefficiency. That is, the corona emitter electrode 121 and the collectorelectrode 122 may be installed in each of the space portions 113, or maybe installed in every two or more space portions 113.

A principle of generating ionic wind in the ionic wind generating unit120 will be described as follows.

Referring to FIG. 1, when the relatively high voltage is applied to thecorona emitter electrode 121, a strong electric field is formed on thecorona emitter electrode 121. If a potential gradient of the electricfield exceeds a certain level, a corona discharge area is formed aroundthe corona emitter electrode 121. Electrons in the corona discharge areaare accelerated to a relatively high speed and collide with airmolecules and as a result the air molecules are separated into positiveions and electrons. Through this process, a corona discharge, that is, adense cloud of positive ions and electrons, is formed around the coronaemitter electrode 121. Here, when the corona emitter electrode 121 is acathode, the positive ions in the corona discharge area are absorbed bythe corona emitter electrode 121 and the electrons are moved from thecorona emitter electrode 121 toward the collector electrode 122 togenerate ionic wind (denoted by an arrow). Thus, forced convection ofnearby air due to the ionic wind transfers heat from the heat radiationpins 120. When the corona emitter electrode 121 is an anode, thepositive ions are moved to generate the ionic wind, which is opposite tothe case where the corona emitter electrode 121 is a cathode.

The negative corona discharge or the positive corona discharge generatesozone (O₃) as a byproduct. Since the negative corona discharge generatesa greater concentration of O₃ than the positive corona discharge, thepositive corona discharge may be preferred; however, it is not limitedthereto. In order to efficiently dissolve O₃ generated as a byproduct bythe negative or positive corona discharge, a catalyst, for example, suchas a manganese (Mn) oxide, a palladium (Pd) compound, or a metal such asPd may be used. To do this, a catalyst layer 130 made of the catalyst isformed to surround the heat radiant 110. In addition, although not shownin drawings, the catalyst may be used on other components installedaround the heat radiant 110.

In addition, since O₃ is formed by using air, the generation of O₃ maybe prevented in an environment where air does not exist. To do this, adevice that may fill an inert gas, for example, such as nitrogen (N) orargon (Ar) into a space around the cooling unit 100 may be installed.The inert gas may prevent degradation of the electrodes.

Referring to FIG. 2, the cooling unit 200 includes a heat radiant 210and an ionic wind generating unit 220. The heat radiant 210 including aheat radiating plate 211 and a plurality of heat radiation pins 212 isattached to a heat element H, and the ionic wind generating unit 220includes a corona emitter electrode 221 and a collector electrode 222installed in a space portion 213 between two adjacent heat radiationpins 212.

The corona emitter electrode 221 is installed on a side surface of atleast one heat radiation pin 212, and the collector electrode 222(denoted by a solid line) is installed to cover an upper half portion ofa side surface of another heat radiation pin 212 that is adjacent to theat least one heat radiation pin 212 on which the corona emitterelectrode 221 is installed to face the corona emitter electrode. Thecollector electrode 222 (denoted by a dotted line) may be installed tocover a lower half portion of the side surface of the another heatradiation pin 212 that is adjacent to the at least one heat radiationpin 212 on which the corona emitter electrode 221 is installed. Thecollector electrode 222 is not limited to an area on the side surface ofthe another heat radiation pin 212 as shown in FIG. 2, and the collectorelectrode 222 may have any of various sizes.

A power unit 223 connects the corona emitter electrode 221 and thecollector electrode 222 to each other, and applies a high voltage to thecorona emitter electrode 221. A catalyst layer 230 made of the catalystis formed to surround the heat radiant 210.

Referring to FIG. 3, the cooling unit 300 includes a heat radiant 310and an ionic wind generating unit 320. The heat radiant 310 including aheat radiating plate 311 and a plurality of heat radiation pins 312 isattached to a heating element H, and the ionic wind generating unit 320includes a corona emitter electrode 321 and a collector electrode 322installed in a space portion 313 between every two adjacent heatradiation pins 312.

The corona emitter electrode 321 may be attached to one of side surfacesof neighboring heat radiation pins 312 that face each other. The coronaemitter electrode 321 may be attached to an upper or middle portion ofthe side surface of at least one heat radiation pin 312. The collectorelectrode 322 may be attached to the heat radiating plate 311 in thespace portion 313. The corona emitter electrode 321 may be installed tobe adjacent to the collector electrode 322, provided that the coronaemitter electrode 321 does not contact the collector electrode 322.

A power unit 323 connects the corona emitter electrode 321 and thecollector electrode 322 to each other, and applies a high voltage to thecorona emitter electrode 321. A catalyst layer 330 made of the catalystis formed to surround the heat radiant 310.

FIG. 4 is a cross-sectional view of a cooling unit 400 according toanother embodiment.

Referring to FIG. 4, the cooling unit 400 includes a heat radiant 410and an ionic wind generating unit 420. The heat radiant 410 including aheat radiating plate 411 and a plurality of heat radiation pins 412 isattached to a heating element H, and the ionic wind generating unit 420includes a corona emitter electrode 421 attached to every other uppersurface of the radiation pins 412 and a collector electrode 422 attachedto the remaining upper surfaces of the heat radiation pins 412. A spaceportion 413 is formed between every two adjacent heat radiation pins412.

The corona emitter electrode 421 may be attached to a random point onthe upper surface of every other heat radiation pin 412, and thecollector electrode 422 may be installed to cover the upper surfaces ofthe remaining heat radiation pins 412.

A power unit 423 connects the corona emitter electrode 421 and thecollector electrode 422 to each other, and applies a high voltage to thecorona emitter electrode 421. A catalyst layer 430 made of the catalystis formed to surround the heat radiant 410.

FIG. 5 is a cross-sectional view of a cooling unit 500 according toanother embodiment, and FIG. 6 is a plan view of a cooling unitaccording to another embodiment.

Referring to FIG. 5, the cooling unit 500 includes a heat radiant 510and an ionic wind generating unit 520. The heat radiant 510 including aheat radiating plate 511 and a plurality of heat radiation pins 512 isattached to a heating element H, and the ionic wind generating unit 520includes a corona emitter electrode 521 and a collector electrode 522installed in a space portion 513 formed between every two adjacent heatradiation pins 512.

The corona emitter electrode 521 may be installed on an upper portion oran intermediate portion in the space portion 513 without contacting theheat radiant 510. Since the corona emitter electrode 521 does notcontact the heat radiation pins 512, the corona emitter electrode 521may be supported by an additional supporting member (not shown) to beinstalled in the space portion 513. The collector electrode 522 may beattached to the heat radiating plate 511 in the space portion 513. Thecorona emitter electrode 521 may be installed to be adjacent to thecollector electrode 522, provided that the corona emitter electrode 521does not contact the collector electrode 522.

A power unit 523 connects the corona emitter electrode 521 and thecollector electrode 522 to each other, and applies a high voltage to thecorona emitter electrode 521. A catalyst layer 530 made of the catalystis formed to surround the heat radiant 510.

Referring to FIG. 6, an entire structure shown in FIG. 6 is similar tothe structure of the cooling unit 500 of FIG. 5. A heat radiant 610includes a heat radiating plate 611 and a plurality of heat radiationpins 612. A collector electrode 622 is attached to the heat radiatingplate 611 in a space portion 613 formed between two adjacent heatradiation pins 612. Although a power unit is not shown in FIG. 6, apower unit similar to the power unit 523 of FIG. 5 may be installed.

However, a corona emitter electrode 621 may be installed at a positiondifferent from that of the corona emitter electrode 521 of FIG. 5. Thatis, the corona emitter electrode 621 is installed in a diagonaldirection of the space portion 613 so as to be slant toward the heatradiation pins 612.

FIG. 7 is a perspective view of a corona emitter electrode 721 accordingto an embodiment, and FIG. 8 is a perspective view of a heat radiant 810according to another embodiment.

Referring to FIG. 7, the corona emitter electrode 721 is formed having asaw-tooth shape in which a plurality of unit electrodes, each formed asa conical shape, are arranged in an array. The saw-tooth shaped coronaemitter electrode 721 may minimize O₃ generation caused by a coronadischarge. This kind of corona emitter electrode 721 may be applied tothe cooling units shown in FIGS. 1 through 6.

Referring to FIG. 8, the heat radiant 810 includes a heat radiatingplate 811, and a plurality of unit heat radiation pins 812 attached onthe heat radiating plate 811. The unit heat radiation pins 812 may beformed by dividing the heat radiation pins 112 of FIG. 1 into aplurality of pieces along a length of the heat radiation pins 112, andthen, spacing the plurality of pieces a predetermined distance apartfrom each other. Accordingly, heat radiation performance may beimproved.

FIG. 9 is a light emitting diode (LED) lighting unit 900 including anionic wind generating unit according to the embodiment.

Referring to FIG. 9, any of the ionic wind generating units according tothe embodiments shown in FIGS. 1 through 6 may be applied to a coolingunit of the LED lighting unit 900. In FIG. 9, the LED lighting unit 900includes the ionic wind generating unit shown in FIG. 1.

The LED lighting unit 900 includes a plurality of LEDs 910 to emitlight, a transparent cover 920 surrounding the LEDs 910 to protect theLEDs 910, a cooling portion 930 including a plurality of heat radiationpins 931 so as to radiate heat generated by the LEDs 910, and a socket940 to connect to an electric power.

A ionic wind generating unit 950 includes corona emitter electrodes 951attached to side surfaces of the heat radiation pins 931, collectorelectrodes 952 attached to side surfaces of the heat radiation pins 931facing the side surfaces on which the corona emitter electrodes 951 areattached, and a power unit 953 to connect the corona emitter electrodes951 to the collector electrodes 952 and to apply a high voltage to thecorona emitter electrodes 951.

Principles of generating ionic wind in the ionic wind generating unit950 are described in the above embodiments, and detailed descriptionsthereof are not provided here.

FIG. 10 is a graph illustrating performance of a cooling unit accordingto an embodiment, FIG. 11 is a graph showing results of measuringvelocity variation of ionic wind in a cooling unit according to anembodiment, and FIG. 12 is a graph illustrating results of measuringtemperature variation of a heat radiant when a cooling unit according toan embodiment operates.

Referring to FIG. 10, using the cooling unit shown in FIG. 5, a tungstenwire having a diameter of 25 μm is installed at an upper location 2.52mm apart from the collector electrode attached to the heat radiatingplate, and a voltage of about 3.5 kV to about 4 kV is applied betweenthe electrodes to generate ionic wind to cool down the heat radiatingplate formed of a ceramic material.

A temperature of the heat radiating plate is cooled down to 74° C. whenthe ionic wind is generated, while the highest temperature of the heatradiating plate is 86° C. when the ionic wind is not generated. Thus,the cooling operation may be performed more efficiently when the ionicwind is generated.

FIG. 11 shows a velocity field of ionic wind, that is, a flow analysisresult showing a cooling effect on a heat radiant coupled to an ionicwind generating unit.

It is assumed that air at a predetermined temperature, for example,300K, is induced under a condition where a heating element is locatedunder a heat radiant and a lower portion of a heat radiation pin isheated constantly. When a corona emitter electrode of an ionic windgenerating unit is located on an upper portion of the heat radiationpin, ionic wind having a velocity of about 1 to 3 m/s is generated evenin a small space having a width of about 3 mm.

When the ionic wind generating unit is located on the heat radiation pinarray in the heat radiant, hot air does not stay around the heatradiation pin, but is moved in a predetermined direction by an air flowinduced by the ionic wind. This becomes an advantage in efficientlycooling down the heating element in a small space.

FIG. 12 shows a temperature distribution cooled down by generation ofionic wind. That is, a heat radiating plate of a cooling unit located ona hot heating element may be efficiently cooled down by the ionic wind.The cooling unit using the ionic wind may efficiently cool down theheating element without generating much noise even in a small space,where it is difficult to use a conventional cooling fan. A heatradiating structure, for example, such as a ceramic heat radiant havingan excellent thermal conductivity and low electrical conductivity may beused instead of a conventional metal heat radiant, or a heat radiantformed by coating ceramic onto a conventional metal heat radiatingstructure may be used in order to directly form a corona emitterelectrode and a collector electrode used to generate the ionic wind on aheat radiant.

While this invention has been particularly shown and described withreference to exemplary embodiments thereof, it will be understood bythose of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the invention as defined by the appended claims.

1. A cooling unit comprising: a heat radiant comprising a heat radiatingplate contacting a heating element, and a plurality of heat radiationpins protruding from the heat radiating plate and separated from eachother with predetermined intervals therebetween, and the heat radiant isformed of an electrical insulating material; and an ionic windgenerating unit comprising a corona emitter electrode contacting atleast one of the heat radiation pins, a collector electrode facing thecorona emitter electrode, and a power unit to connect the corona emitterelectrode to the collector electrode and apply a high voltage to thecorona emitter electrode.
 2. The cooling unit of claim 1, wherein thecorona emitter electrode is attached to a point on a side surface of oneof two adjacent heat radiation pins, and the collector electrode isattached to a side surface of the other heat radiation pin to face thecorona emitter electrode.
 3. The cooling unit of claim 2, wherein thecollector electrode is attached to an upper portion or a lower portionof at least one heat radiation pin.
 4. The cooling unit of claim 2,wherein the collector electrode is installed to contact the heatradiating plate between two adjacent heat radiation pins.
 5. The coolingunit of claim 1, wherein the corona emitter electrode is attached to anupper surface on one of two adjacent heat radiation pins, and thecollector electrode is attached to an upper surface of the other heatradiation pin.
 6. The cooling unit of claim 1, wherein the coronaemitter electrode is formed of a wire having a circular cross-section.7. The cooling unit of claim 1, wherein the corona emitter electrode isformed having a saw-tooth shape.
 8. The cooling unit of claim 1, whereineach of the heat radiation pins is divided into a plurality of unitradiation pins in a length direction of the heat radiation pins.
 9. Thecooling unit of claim 1, wherein the heat radiant is coated with acatalyst that dissolves ozone (O₃) generated as a byproduct when theionic wind generating unit operates.
 10. The cooling unit of claim 1,wherein the heat radiant is formed of a ceramic material.
 11. Thecooling unit of claim 1, wherein the heat radiant is formed by coatingan electrical insulating material on a conductive material.
 12. Acooling unit comprising: a heat radiant comprising a heat radiatingplate contacting a heating element, and a plurality of heat radiationpins protruding from the heat radiating plate and separated from eachother with predetermined intervals therebetween, and the heat radiant isformed of an electrical insulating material; and an ionic windgenerating unit comprising a corona emitter electrode disposed at apoint along a protruding direction of the heat radiation pin in apredetermined space formed between adjacent heat radiation pins, acollector electrode facing the corona emitter electrode, and a powerunit to connect the corona emitter electrode to the collector electrodeand apply a high voltage to the corona emitter electrode.
 13. Thecooling unit of claim 12, wherein the collector electrode is installedto contact the heat radiating plate between two adjacent heat radiationpins.
 14. The cooling unit of claim 13, wherein the corona emitterelectrode is disposed diagonally along a length direction of the heatradiation pins in the predetermined space.
 15. The cooling unit of claim12, wherein the corona emitter electrode is formed of a wire having acircular cross-section.
 16. The cooling unit of claim 12, wherein thecorona emitter electrode is formed having a saw-tooth shape.
 17. Thecooling unit of claim 12, wherein each of the heat radiation pins isdivided into a plurality of unit radiation pins in a length direction ofthe heat radiation pins.
 18. The cooling unit of claim 12, wherein theheat radiant is coated with a catalyst that dissolves O₃ generated as abyproduct when the ionic wind generating unit operates.
 19. The coolingunit of claim 12, wherein the heat radiant is formed of a ceramicmaterial.
 20. The cooling unit of claim 12, wherein the heat radiant isformed by coating an electrical insulating material on a conductivematerial.
 21. A light emitting diode (LED) lighting unit comprising: atleast one LED; a cooling unit comprising a plurality of heat radiationpins to radiate heat generated by the LED; and an ionic wind generatingunit comprising a corona emitter electrode contacting at least one ofthe heat radiation pins, a collector electrode facing the corona emitterelectrode, and a power unit to connect the corona emitter electrode tothe collector electrode and apply a high voltage to the corona emitterelectrode.
 22. The LED lighting unit of claim 21, wherein the coronaemitter electrode is attached to a point on a side surface of one of twoadjacent heat radiation pins, and the collector electrode is attached toa side surface of the other heat radiation pin.
 23. The cooling unit ofclaim 9, wherein the catalyst is manganese (Mn) oxide, palladium (Pd) orPd compound, wherein a catalyst layer made of the catalyst is formed tosurround the heat radiant.
 24. The cooling unit of claim 18, wherein thecatalyst is Mn oxide, Pd or Pd compound, wherein a catalyst layer madeof the catalyst is formed to surround the heat radiant.
 25. The coolingunit of claim 1, wherein an inert gas is provided into a space aroundthe cooling unit to prevent the generation of O₃.
 26. The cooling unitof claim 12, wherein the corona emitter electrode does not contact theheat radiant and the collector electrode.
 27. The cooling unit of claim14, wherein the corona emitter electrode does not contact the heatradiant and the collector electrode.
 28. The cooling unit of claim 1,wherein the corona emitter electrode is installed on the lower portionof the side surface of the at least one of plurality of heat radiationpins.
 29. The cooling unit of claim 1, wherein the corona emitterelectrode does not contact the collector electrode.